KR970006185B1 - Disk discrimination method optical disc reproducing device - Google Patents

Abstract

A method for determining a magnitude a disk of an optical disk playing apparatus having a spindle motor(4), a light pickup unit(6), a RF amplifier(10), a servo signal processor(8), a digital signal processor(12), a microcomputer(16) and a digital/analog converter(14), is disclosed. The method comprises a step of counting a constant linear velocity lock time until the linear velocity lock time signal is generated; a step of counting a breaking time until a breaking time signal is generated; and a step of determining the magnitude of the disk by comparing both a constant velocity lock time and a breaking time to a predetermined reference time corresponding to each of the disk magnitudes. Thereby, the magnitude of the disk can be simply determined.

Description

Disc size determination method of optical disc player

1 is a block diagram of a general optical disc reproducing apparatus to which the present invention is applied.

2 is a process flowchart of disc size determination in accordance with the present invention.

The present invention relates to an optical disc reproducing apparatus for reproducing a signal recorded on a disc, and more particularly to a method for determining the size of a disc currently mounted in an optical disc reproducing apparatus that can also use a disc of a different size. will be.

In general, an optical disc reproducing apparatus refers to an apparatus that reproduces information recorded on a disc such as a CDP (Compact Disc Player), LDP (Laser Disc Player), etc. by an optical method. Discs used in this case include CDs (Compact Discs) and LDs (Laser Discs). Here, the sizes of the disks, i.e., the diameters, are not all the same but can be selected as necessary. For example, the size of the CD is divided into 8cm, 12cm in diameter and the size of the LD is divided into 20cm, 30cm in diameter.

As described above, since the size of the disc is various, the optical disc reproducing apparatus determines the size of the disc to be loaded during the reproducing operation and then performs appropriate control for the determined disc size. For example, in a high-speed search using the track count method, the gain for a constant linear velocity (CLV) servo is adjusted according to the size of a disk. This is to apply the CLV gain differently according to the size of the disk because the weight of the disk varies. In the CDP, if the diameter of the CD is 8 cm, the CLV gain is adjusted lower than that of 12 cm.

In the optical disc reproducing apparatus, there has been a technique of using a sensor as a technique for determining the size of a disc. This is to determine the size of the disk by installing the sensor at a position away from the central axis of the disk to turn the sensor on or off according to the size of the disk to be mounted. For example, in case of CDP, if the sensor is installed 5cm away from the central axis, the size of the disk can be determined by turning off the sensor when the CD with 8cm diameter is mounted and the sensor is turned on when the CD with 12cm diameter is installed. Will be. However, such a technology requires not only an element such as a sensor but also requires a part or a space for installing the sensor.

Another technique for determining the size of a disc has been the use of focus servos. This determines the size of the disk by checking whether a focus drop has occurred while moving the long pick-up device from the inner circumference of the disk to the outer circumferential position corresponding to the maximum size of the disk that can be mounted in the focus-on state. For example, in case of CDP, while moving the optical pickup device to the outer periphery position 6cm away from the center of the disk, if the focus drop does not occur, the disk is determined to be 12cm in diameter. The size of 8 cm is determined. In this case, if focus drop occurs, refocus is repeated several times at the position where the focus drop occurs to improve reliability. However, such a technique has a problem in that, when the size of the disc is small, the time for starting to reproduce the actual information is delayed as the refocus is repeated several times unnecessarily.

Another technique for determining the size of a disk has been the use of CLV lock times.

This determines the size of the disk by the size of the CLV lock time, which is the time taken from the time when the disk is started from the stationary rotation to the predetermined CLV and locked. CLV lock times are longer for heavier discs and shorter for lighter ones. Typically, the CLV lock time is about 450 msec for a CD with a diameter of 8 cm and about 850 msec for a CD with a diameter of 12 cm. Therefore, if the size of the disc is different, the weight is different, and if the weight is different, the size of the disc is determined by using the CLV lock time. However, such a technique has a problem in that accuracy is reduced by using only the CLV lock time, and when a part of the disk is damaged, the size of the disk is incorrectly determined.

Accordingly, an object of the present invention is to provide a method for easily and accurately determining the size of a disc in a disc size determination method of an optical disc reproducing apparatus without adding a separate component.

The present invention for achieving the above object is a first counting process for counting the CLV lock time from the standstill state to start the acceleration rotation to reach the predetermined first CLV, and to rotate the disk to the first CLV The second counting process of counting the braking time from the state to the deceleration rotation until reaching the preset second CLV, and the unique reference time corresponding to the size of the disc, respectively, And a discriminant process of discriminating the size of the disc by comparing with.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

In the following description, for the convenience of explanation, the present invention will be described with an example of applying the present invention to a CDP, which is one of the optical disc reproducing apparatuses.

Fig. 1 shows a block diagram of a general optical disc reproducing apparatus to which the present invention is applied, and shows a schematic block arrangement of an example of a CDP. In FIG. 1 a spindle motor 4 is driven by the control of a servo signal processor 8 to rotate the disk 2. The optical pickup device 6 picks up the information recorded on the disk 2 by an optical method and applies it to the RF (Rodio Frequency) amplifier 10. The servo signal processor 8 controls the tracking servo, the focus servo, the sled servo, etc. of the optical pickup device 6 by the control of the microcomputer 16 and the output signal of the RF amplifier 10. It processes the signals for the, and drives the spindle motor (4) by the output signal of the digital signal processor (12). As the servo signal processing section 8, CXA1082, CXA1182, CXD1182, etc. which are dedicated LSIs are used. The RF amplifier 10 amplifies the RF signal picked up by the optical pickup device 6. The digital signal processor 12 forms and demodulates the RF signal amplified by the RF damper 10 into an EFM (Eight to Fourteen Modulation) waveform. The digital signal processing unit 12 also generates a CLV lock signal when the disk 2 is stopped and accelerates and reaches the first CLV. The digital signal processor 12 decelerates and rotates when the disk 2 reaches the first CLV to reach the second CLV. Occurs. Here, the first CLV refers to a CLV capable of normally reproducing information recorded on the disc 2, and the second CLV refers to a CLV in which the disc 2 can be stopped in a deceleration rotation state. As the digital signal processor 12, a dedicated LSI, CXDl130, or the like is used. In the CXD1130, a CLV lock signal is generated as a GFS signal of a logic low, and a braking signal is generated from a logic low. Occurs as a signal. The D / A converter 14 converts the signal demodulated by the digital signal processor 12 into an analog signal and outputs the analog signal. The microcomputer 16 generally controls the reproduction operations of the servo signal processing section 8 and the digital signal processing section 12 in order to reproduce the information recorded on the disc 2.

On the other hand, the configuration of FIG. 1 is shown on page 240 of the Illustrated Compact Disc, which is issued and sold on September 1, 1988 by Ganam, South Korea. For more detailed configuration and operation of the CDP, refer to the illustrated compact disc. Just do it.

FIG. 2 is a flowchart of disc size determination in one embodiment according to the present invention, which is performed in the microcomputer 16 of FIG. In step 202 of FIG. 2, the disk 2 starts to accelerate rotation from a stop state, and in step 204, the CLV lock time is started counting, and in step 206, the CLV lock time is counted. Check if the CLV lock signal is input. If the CLV lock signal is not input, step 206 is continued. If the CLV lock signal is input, step 210 is performed. In step 210, the counting of the CLV lock time is stopped, and if the CLV lock time counted up to that time is greater than the first reference time in step 212, the first size flag is entered in step 214. Set L_FLG. After that, in step 218, the disk 2 is rotated to the first CLV, and the deceleration rotation is started, and in step 220, the braking time is counted. In step 222, the braking time is counted. In the step, it is checked whether a braking signal is input. If the braking signal is not input, step 222 is continued, and if the braking signal is input, step 220 is performed. In step 226, the braking time counted up to that time is compared with the second reference time in step 228, and if step is greater than the second reference time, step 230 is performed; if it is smaller than the second reference time, step 234 is performed. do. In operation 230, the state of the first size flag L_FLG is inspected, and in the reset state, operation 202 is performed. In operation 232, the size of the disk 2 is determined in operation 232. . In operation 234, the state of the second size flag S_FLG is inspected, and in the reset state, operation 202 is performed. In operation 236, the size of the disk 2 is determined as the second size.

Hereinafter, with reference to FIGS. 1 and 2 attached to an operation example of the present invention will be described in detail.

First, when the disc 2 is settled and a play button (not shown) is pressed, the microcomputer 16 controls the servo signal processing unit 8 to focus on the optical pickup device 6 in FIG. Step 202) is performed.

In step 202, the microcomputer 16 starts the rotational rotation of the spindle motor 4 through the servo signal processor 8. Accordingly, the disc 2 is accelerated from the stationary state. Next, the microcomputer 16 starts counting the CLV lock time from the initial value in step 204, and then locks the CLV lock from the digital signal processing unit 12 while continuing to count the CLV lock time in steps 206 to 208. Check that a signal is generated and input. At this time, the digital signal processing unit 12 detects the CLV of the disc 2 from the reproduction signal picked up by the optical pickup device 6 and input through the RF amplifier 10. When the disk 2 is continuously accelerated and rotated to reach the first CLV and locked, the digital signal processing unit 12 generates a logic low GFS signal as a CLV lock signal and applies it to the microcomputer 16. Then, the microcomputer 16 stops counting the CLV lock time in step 210 and compares the CLV lock time counted up to that time in step 212 with the first reference time. Here, the first reference time is set to an inherent time value corresponding to the size of the dask 2, for example, in the case of a CD, the CLV lock time is about 450 msec in the case of a CD having a diameter of 8 cm as described above. In the case of 12cm CD, the first reference time may be set to 650msec since it is about 850msec. In this case, when the CLV lock time is greater than the first reference time, the first size flag L_FLG is set in step 214, and when the CLV lock time is smaller than the first reference time, the second size flag S_FLG is set in step 216. Here, the first size flag L_FLG and the second size flag S_FLG use a register inside the microcomputer 16, and the initial value is reset. Therefore, the size of the disk 2 is distinguished by one month. That is, when the disk 2 is a CD, if the CLV lock time is greater than the first reference time, the size of the disk 2 is divided into 12 cm in diameter. If the disk 2 is smaller than the first reference time, the size of the disk 2 is 8 cm in diameter. It is distinguished to be.

However, when determining the size of the disk 2 using only the CLV lock time, the accuracy is inferior as described above, and when a part of the disk is damaged, the size of the disk is incorrectly determined (218)-( Step 236) is further performed.

In step 218, the microcomputer 16 starts the deceleration rotation of the spindle motor 4 rotating in the first CLV through the servo signal processing unit 8. As a result, the disk 2 is decelerated and rotated in the first CLV. Next, after the microcomputer 16 starts counting the braking time from the initial value in step 220, the braking signal is generated from the digital signal processor 12 while continuously counting the braking time in steps 220 and 224. To check if it is entered. When the disc 2 continues to decelerate and reaches the second CLV, the digital signal processing unit 12 The signal is generated as a braking signal and applied to the microcomputer 16. Then, the microcomputer 16 stops counting the braking time in step 226 and compares the braking time counted up to that time in step 228 with the second reference time. Here, the second reference time is set to an intrinsic potential time value corresponding to the size of the disc 2 similarly to the first reference time. If the braking time is greater than the 26th reference time, the state of the first size flag L_FLG is examined in step 230, and the disc 2 has the size of the first diameter in step 232 of the set state. Determine. On the other hand, when the braking time is smaller than the second reference time, the state of the second size flag S_FLG is examined and it is determined in step 236 that the disc 2 is a disc having the size of the second diameter.

Here, the first diameter is larger than the second diameter. If the first size flag L_FLG is in the reset state in step 230 or the second size flag S_FLG is in the reset state in step 234, the operation as described above is performed again from step 202.

Therefore, the size of the disk 2 can be accurately determined by discriminating the size of the disk 2 by the CLV lock time and the braking time. That is, in the case of a CD, the size of the disc 2 can be accurately determined by the CLV lock time and the braking time only when the CLV lock time is greater than the first reference time and the braking time is greater than the second reference time. You can determine the cookie. That is, in the case of CD, the size of the disc 2 is determined to be 12 cm in diameter only when the CLV lock time is greater than the first reference time and the braking time is greater than the second reference time, and the CLV lock time is larger than the first reference time. It is discriminated that the size of the disc 2 is 8 cm in diameter only when it is small and the braking time is smaller than the second reference time.

As described above, the present invention has the advantage that the disc size determination method of the optical disc reproducing apparatus can easily and accurately determine the size of the disc in the existing optical disc reproducing apparatus without adding a separate component.

Meanwhile, in the above description of the present invention, specific embodiments have been described, but various modifications can be made without departing from the scope of the present invention. In particular, when the disc size is two kinds of discrimination is illustrated, it can be seen that all of the devices that can be used for the disc divided into more types. In this case, the reference time for the CLV lock time and the braking time may be subdivided according to the type of disc. Therefore, the scope of the invention should not be defined by the described embodiments, but should be defined by the equivalents of the claims and the claims.

Claims (5)

The disks of different sizes are combined, and when the disk is locked at the first fixed speed by accelerating rotation in the stationary state, the fixed speed lock signal is generated, and the disk is decelerated and rotated while the disk rotates at the first fixed speed. A disc size discriminating method of an optical disc reproducing apparatus, comprising means for generating a braking signal when a fixed speed is reached, wherein the fixed speed starts until the fixed speed lock signal is generated by starting the rotation from the stop state of the disc. A first counting step of counting a lock lock time, a second counting step of counting a braking time until the braking signal is generated by starting a deceleration rotation from the state in which the disk is rotated at the first predetermined speed; Comparing the counted fixed speed lock time and the braking time with a unique reference view corresponding to the size of the disk, respectively. By a disc size detection method which comprises a determination process that determines the size of the disk. The disc size discrimination method according to claim 1, wherein the discrimining process determines the disc as the corresponding size only when the counted fixed speed lock time and the braking time correspond to the reference time for the disc of the same size. . The disks of different sizes are combined, and when the disk is locked at the first fixed speed by the acceleration and rotation in the stationary state, the fixed speed lock signal is generated, and the disk is decelerated and rotated while the disk is rotated at the first fixed speed. A disc size discriminating method of an optical disc reproducing apparatus having means for generating a braking signal when a fixed speed is reached, wherein the fixed speed from the standstill state to an acceleration rotation until the fixed speed lock signal is generated A first counting process for counting a lock time, a first comparison process for comparing the counted fixed speed lock time with a first reference time, and the fixed speed lock time in the first comparison process is greater than the first reference time. If large, the first size set process of setting the first size flag and the fixed speed lock time in the first comparison process are the first reference time. If it is smaller than the interval, the second size set process of setting the first size flag, and the braking time until the braking signal is generated by starting the deceleration rotation from the state in which the disc is rotated at the first fixed speed, are counted. A second count process, a second comparison process for comparing the counted braking time with a second reference time, and the first size flag when the braking time is greater than the second reference time in the second comparison process. In the first judging process of determining that the disc is of the first size only in a set state by checking a state of the state, and when the braking time is smaller than the second reference time in the first comparison process, And a second judging step of judging a state and determining that the disc is of a second size only at a set state. 4. The method of claim 3, wherein the first size of the first determination process is larger than the second size of the second determination process. The method of claim 4, further comprising: performing the process again from the first counting process when the first flag is in the reset state in the first discrimination process or when the second flag is in the reset state in the second discrimination process. Disc size determination method characterized in that.